I have converted an ASP.net Web Application (not Web Site) to .Net 4.0 from .Net 3.5 without any hassles.
When I deploy it to a test server, it worked, although when I deploy it to our production server it gives me the following error.
"Could not load type 'ADODB.FieldsToInternalFieldsMarshaler' from assembly 'ProjectX, Version=1.0.4113.15225, Culture=neutral,
I did experience errors on the test server but I was able to resolve this by:
Compiling my web application as a 32 bit
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